Manufacture of lead arsenate.



, being herein explained and the Enn s names,

cent-men"- A,

To all whom it nmy concern:

Be it known that I, PAULZK miss, a citizen of the United States, of Lakewood, county of Cnyeho State of Ohio, have invented ne J i useful Improvement in the Men" A an 0. Lead Arsenete, of which the iiolion ing" s e speclficetion, the principle of the invention eerie in which I have contemplated sp principle, so as to distinguish inventions.

Lead arsenste may be made by ciirectly reacting upon iitherge, that is lead ()Xiii. of the formula PM), With arsenic acicl "59g, such reaction beino' indicated by the follow ing equation, viz

PbO+H,AsG,:PbHAsO,+-H

I have discovered, however, that a much superior product is obtained, and the reaction moreover considerably expedited, by adding another ingredient to the two me.- terials just named, such other ingretiient consisting of a halogen derivative oi silicon, preferably an acid-halogen derivative such as hydro-iluosiliciq acid (H SiF L In carrying out the manufacture, then, oi arsenete in accordance with my present proved method, I utilize the steps 1 '1 after fully described and particularly pointed out in the claims.

The following description sets forth in detail on approved method of carrying out the invention, such disclosed mode, however, constituting but one of the various Ways in which the principle of the invention may be used. c

The lithmge and arsenic acid are preferably used in the proportions of their combining weights, it being understood that such combinin Weights ere slightly diffen ent for the difierent ersenetes, Vin, so-celieci acid ersenete and neutral sir-senate, ordinary commercial arsenete of lead usually consisting of a mixture of the two. P neretcry to the reaction the iitherge Water so as to make a rather then the proper mnonnt of added, anti linsliy e rele Specification of jiittess which consists in reacting be 0" tie h rlrofinosiiicie acid. er

one cane, i'or ensnieie used. es

' iiytiroiiuosilicie -5 e ieeci tn i ei i, snico tic is soluble in water, which turn reacts with the arsenic presen e mixture to form lead arsenete ,Ineic to this inst reaction liytirofinosilicie e reformed, which in turn acts on ,hwe reactions, as previous v cur rapidly, and the the let when formed the fesh en loscribed, is at very superior product, it is a soft, flaky White precipitate i readily snspendeqi in Water with little tennency to settle, and so cdmirehi suited, io use es en insecticide.

Uther anodes of applying the principle o my invention may be employed ins-teed c the one expiaineti, change being mede as re gerds the steps or mechanism herein disclosed, provided the means steteti by any of the following claims or the equiveient of such stated means he employeti,

i therefore particularly point out and, dis" tinctly claim as my invention 1, The ethoti of making iced e, which consists in i'eecti. between. i and arsenic eeid in the presence 0; so halogen tierivetive of silicon,

E3. method oi making arse? which consists in reacting be t and arsenic cici in the presence 0 iiuosilicic acid, substantially {LS descr 3, The method nieicii and arsenic acid, used in tile proportions their combining weights, in the presence of hydroiiuosilicic acid, the latter being used in an amount less than one per cent. of such acid.

Signed by me this 24th day oY fniy, 191G,

KEN 

